1. Field of the Invention
The present invention relates to an electrolyte for a lithium ion capacitor and a lithium ion capacitor including the same, and more particularly, to an electrolyte for a high-capacity and low-resistance lithium ion capacitor and a lithium ion capacitor including the same.
2. Description of the Related Art
A stable supply of energy is one of the most important factors in the operation of various electronic products such as information telecommunication devices. Generally, the function is performed by a capacitor. That is, the capacitor serves to charge and discharge electricity in and from circuits of information telecommunication devices and various other electronic products, thereby making it possible to stabilize the electricity flow in the circuits. The general capacitor has a very short charging and discharging time and a long lifespan but has a limitation when being used as a storage device due to a high output density and a small energy density.
In order to overcome this limitation, a new capacitor such as an electric double layer capacitor having a very short charging and discharging time and the high output density has recently been developed, which recently drawn much attention as a next-generation energy device, together with a rechargeable battery.
Recently, various electrochemical capacitors operated on a principle similar to the electric double layer capacitor have been developed and an energy storage device called a hybrid capacitor, according to a combination of charging principles of the lithium ion rechargeable battery and the electric double layer capacitor, has come into prominence. Consequently the hybrid capacitor, a lithium ion capacitor having the high energy density of a rechargeable battery and the high output characteristics of an electric double layer capacitor has recently been prominent.
The lithium ion capacitor contacts an anode capable of absorbing and separating lithium ions to a lithium metal to previously absorb (or, dope) the lithium ions in the anode by using a chemical method or an electrochemical method, and lowers a cathode potential to increase the withstand voltage and remarkably increase the energy density.
However, when the electrolyte used in the rechargeable battery of the related art is used in the lithium ion capacitor, there are problems in that the capacity thereof is degraded, the resistance is increased, and the output characteristics are degraded, under the low temperature.